The Processor used in the HP Compaq D330 series of desktop computers is an intel Pentium 4.
The older style of Pentium 4 that uses a Socket 478, processor socket.
There were three different styles, of the HP Compaq D330 desktop computers made.
1) Desktop style:
Looks like a 'Pizza Box', and lays flat on the computer desk.
2) Microtower style:
A small tower style computer case
3) Slimtower style:
A small tower style case that is narrow in width, and shorter in height than the Microtower.
Reason I brought this up, is the fan design changes from style to style.
One style uses a fan which attaches to the Heatsink with screws.
(Heatsink is the finned metal unit under the fan, and sits directly on the Processor)
The other style has a plastic baffle that surrounds the fan. (Black in color if memory serves)
(The Baffle is a round plastic part that surrounds the fan blades. It directs the air flow. My term would be - fan shroud, as in used on a car)
Again going by memory, but I believe the baffle is a two part unit. There is a top half, and a bottom half.
Once the Heatsink/Fan Assembly is removed from the Processor socket, I think you can access two screw heads, coming up from the bottom.
Removing the two screws allows the Baffle to be separated, and allows access to the fan.
I believe there is also a tab on the top half of the Baffle, which a U shaped part from the bottom half of the Baffle, locks over the tab.
The U shaped part is a Lock.
(May be two tabs, and two U shaped locks. One on each side)
The U shaped part is gently pried out towards the outside, which allows the tab to slide free.
The two halves could also be glued together.
If your reference is to just clean the fan, after removing the Heatsink/Fan Assembly from the processor socket, I would use Q-tips, and a can of compressed air for computers, to clean it.
When using the can of compressed air I advise using short bursts.
The fan is only designed to spin so fast, and spinning it faster than it was designed for, can lead to premature failure of the fan's bearings.
If your reference is to replace the fan due to the fan's bearings have failed, my advice would be to replace the Heatsink/Fan as a unit.
There are much better models out there than this factory one.
Also accessing an original fan, will lead to buying the complete Fan/Baffle assembly.
1) You may be able to find it on a website like Ebay.
2) It will probably be a pull off of an old computer, and who knows what the lifespan will be?
BEFORE the Heatisnk/Fan Assembly is reinstalled;
The bottom of the Heatsink, and the top of the Processor case must be Thoroughly cleaned!
Also fresh new Thermal Paste must be applied, and correctly.
Thermal paste is around $2 to $4 at a local computer repair shop. It should come in a small tube, and enough for one application.
Should you need advice on how to properly apply thermal paste, let me know in a Comment.
If there is a white thermal pad being used, take it off, throw it away. These cannot be reused, and are junk to begin with.
I use an old plastic credit card to scrape the Heatsink bottom, and the top of the Processor case. Then I use Q-tips dipped in Isopropyl Alcohol to help clean. (Rubbing alcohol)
Takes a few Q-tips.
BEFORE you reach inside your computer, have the computer unplugged from power, AND touch the metal frame of the open computer case.
Your body carries Static electricity, and Static will fry out computer hardware components.
Especially a Processor.
Touch the metal frame of the computer case to relieve your body of Static.
If you get up, and walk away, when you return touch the metal frame again.
To Remove the Heatsink/Fan Assembly from the processor socket:
Looking at the processor socket you will note that there are four H shaped brackets.
These are plastic, and are formed into the base of the processor socket.
There is one in each corner.
The H shaped bracket has a slot hole in the middle of the bracket, towards the top.
The Heatsink/Fan Assembly has a tab that lines up with that slot hole.
Four tabs on the Heatsink/Fan Assembly corners, to match the four H shaped brackets.
The top of the H shaped bracket is - Gently pried towards the outside.
Very gently as it's plastic, and is brittle from the heat inside the computer all these years.
The H shaped bracket is just pried out far enough to clear, the tab of the Heatsink/Fan Assembly.
Once two tabs are released, the Heatsink/Fan Assembly can be tilted a little, and lifted up, and out.
This gives you a closer view of that Socket 478 bracket not installed,http://www.directron.com/heatsinkholder.html
(You can click on the photos to enlarge them)
I would like you to go here to Manual Shark, and download (Free) the
Technical Reference Guide, for the HP Compaq D330 series of desktop
On this page above the large yellow - Manual Details heading is - Download. Left-click on Download.
(To the left of Download is an Adobe PDF icon)
This is a PDF file download. (The computer you are using now has Adobe Reader on it, which uses PDF files)
You may not see anything happening for up to 20 seconds.
Please be patient as the PDF file is downloading in the background.
Once it finishes downloading, the file will come up on your screen.
With this guide you'll see the Heatsink/Fan Assembly, and a closer look at how to remove it.